Microsoft Office 2010 Online to Work on Safari... How About Mobile Safari for iPhone?

Microsoft – the king of paid software – will announce today that it is going to give a version of Office away for free online. Both the online and desktop versions are scheduled to arrive in the first half of next year. Yes, you read that right. The latest version of its ubiquitous productivity software, dubbed Office 2010, will come as both a piece of software you can buy for your computer, and as a service you can access in your browser. [UPDATE: Microsoft says it will support the Firefox and Safari browsers as well as IE.]

Which immediately makes us ask -- how about Mobile Safari?

While native Office-supporting apps are obviously the way to go for many people, Google Docs has proven a place and usage case for WebApps, and having Microsoft Office 2010, of all things, as a WebApp on the iPhone would no doubt appeal to many, many users as well.

(Not to mention WebKit, the engine behind Mobile Safari, is also used by Android, Palm, and some Nokia devices, which would certainly be additional eyeballs for Microsoft's ad sponsorships.)

I wonder if Office 2010 will only support cloud storage of documents. And If so, where?
Google Docs really intends to support cloud based storage. Yes, you can download it and upload it each time, but that is pretty much a total pain in the rear. Its designed for storing on google's servers.
And for the most part Google Docs works well in Safari.
(I have used Google Docs for several 600 page PDF manuals I like to have available from everywhere. I the can be accessed in Safari reasonably well.)
Will anyone be willing to trust Microsoft with their documents if Office 2010 also stores in the Cloud? Or will Microsoft make it more friendly to local storage?